"There was a man sent from God, whose name was John. This man came for a witness, to bear witness of the Light, that all through him might believe. He was not that Light, but was sent to bear witness of that Light." (vv.6-8)
There was a man sent from God: John the Baptist bore witness of the light, that all through him might believe. The work of John the Baptist was deliberately focused on bringing people to faith in Jesus the Messiah. The testimony of John is introduced not only as a historical note, but in order to bring out the aggravated blindness of those who rejected Christ.
He was not that light, but was sent to bear witness of that light. The matter of witness is a serious thing, it establishes truth and gives ground for faith. Yet, being a witness does more. It commits a man. If one takes a stand in the witness box and testifies that such-and-such is the truth of the mater, one is no longer neutral, but committed. The Apostle John lets us know that there are those like John the Baptist who have committed themselves by their witness to Christ.
John the Baptist's work was remarkably well received and widely known. Yet in our text the writer still makes it very clear that John the Baptist was not the Light spoken of here in verses 6-8, but that he pointed towards and bore witness of that Light to come. The "true light" that gives light to everyone was coming into the world (v.9). He goes on to say that, "He was in the world, and though the world was made through Him, the world did not recognize Him" (v.10). God came to the same world He created, to the creatures made in His image, and yet the world did not know Him.
While this is extremely sad, sadder still will be the day in which God rejects those of His creation seeking to enter the kingdom of heaven whom He never knew.
The Truth: "Many will say to Me in that day, 'LORD, LORD! And then I will say to them, 'I never knew you; depart from Me, you who practice evil!' (Matthew 7:23)
